Wireless communication systems are widely deployed to provide various types of communication, such as voice and data communications. These systems may be based on a variety of modulation techniques, such as code division multiple access (CDMA), time division multiple access (TDMA), or frequency division multiple access (FDMA). A CDMA system provides certain advantages over other types of systems, including increased system capacity.
A CDMA system may be designed to support one or more CDMA standards such as (1) the “TIA/EIA-95-B Mobile Station-Base Station Compatibility Standard for Dual-Mode Wideband Spread Spectrum Cellular System” (the IS-95 standard), (2) the standard offered by a consortium named “3rd Generation Partnership Project” (3GPP) and embodied in a set of documents including Document Nos. 3G TS 25.211, 3G TS 25.212, 3G TS 25.213, and 3G TS 25.214 (the W-CDMA standard), (3) the standard offered by a consortium named “3rd Generation Partnership Project 2” (3GPP2) and embodied in a set of documents including “C.S0002-A Physical Layer Standard for cdma2000 Spread Spectrum Systems,” the “C.S0005-A Upper Layer (Layer 3) Signaling Standard for cdma2000 Spread Spectrum Systems,” and the “C.S0024 cdma2000 High Rate Packet Data Air Interface Specification” (the cdma2000 standard), and (4) some other standards.
A CDMA system that supports that cdma2000 standard may include support for a number of specifications, including, for example, the IS856 specification for high data rate (HDR) wireless communications, also known as the 1xEV specification, and the IS2000-1x specification for voice and data communications.
The IS856 standard provides high data rate services to data only wireless communication devices (WCDs) or to WCDs known as hybrid access terminals (HATs), which support multiple standards, possibly including the IS2000-1x standard. An IS856-compliant system can be co-located or overlaid in some other manner with an IS2000-1x network to provide enhanced high-speed data services. The separation between the IS856 and IS2000-1x systems is realized in the frequency domain in a similar manner to the separation between cdma2000 system channels. The IS856 and IS2000-1x standards, however, do not provide for compatibility between the two systems.